Film, or other photosensitive media, is commonly used in a number of environments ranging from the photographic industry to more commercial uses such as micrographic imagers. It is in the commercial industry, particularly in the use of what is known as laser COM film that the present invention has particular utility.
Film is commonly available in canisters which provide an easy mechanism for the user to handle the film without being in a safe light environment such as red light or light tight dark room conditions, i.e., in an environment so sufficiently devoid of light that the film will not be appreciably exposed. The laser COM film may be purchased, or supplied, from the film manufacturer or distributor already contained in a canister suitable for insertion directly into the laser imager using the film. Typically, the film is configured inside the canister on a roll.
Typically the canister will contain enough film for a plurality of images, e.g., an entire roll of images. When the film is entirely dispensed or used, or earlier if desired by the user, the film must be replaced by the user. The canister containing the spent roll can be simply removed from the machine and a canister containing fresh film can be installed in its place.
The used canister must either then be discarded or reloaded with fresh film, either on the premises by the user or customer or elsewhere by another party. Usually, the canister is tightly closed and secured to provide a light tight environment for the film. Typically, the canister is discarded since it otherwise would be broken in disassembly and removal of the spent roll and must be discarded.
U.S. Pat. No. 4,671,409, Espy, discloses a light tight film canister disposed to hold rolls of microfilm used in reader/printers. The film canister disclosed in the Espy patent is press fit and snapped together in a manner which will not allow disassembly and reuse of the canister. The canister disclosed in Espy is configured to hold rolls of microfilm used in reader/printers, includes a tubular sleeve closed at both ends by opaque end caps. The end caps are lockingly interconnected by a rigid tie bar that extends between the end caps through the roll of film. This tie bar includes a pair of resilient fingers on each of its opposite ends. During assembly of the canister, these resilient fingers are deformed under pressure and snapped into central apertures in the end caps.
There is a problem, however, on what to do with the used film canister. Typically, used film canisters are simply discarded. This, however, results in a significant cost and a waste of precious earth resources as well as creating a disposal hazard. Thus, it would be desirable to be able to reuse the canister by loading the canister with fresh film and returning the reused and refilled canister to use.
Canisters have been constructed which have been intended for reuse. For example, U.S. Pat. No. 3,771,687, Krtous, discloses a cylindrically shaped cartridge for retaining photographic film in coiled form. The cartridge is open ended and includes a pair of parallel side walls. The edges of each of the side walls define opposing latching channels. The outwardly disposed surface of each of the walls defines a pair of spaced recesses positioned adjacent the edge of the respective wall. A cover is hinged to the cartridge housing and each side of the cover carries a pair of ears for engagement with the recesses. Formed at each side of the cover is a flange for locking engagement with its respective channel. However, the canister disclosed in Krtous is not light tight and does not have need to be refilled in a dark room environment.
Other canisters have been constructed which are intended for reuse and which must be refilled in a dark room environment.
For example, U.S. Pat. No. 4,420,120, Raymond, discloses a cassette including a housing formed of a pair of mating shells which join to define a cylindrical chamber to confine sheet photographic materials, such as negative active film, emulsified paper and the like. The shells are hingedly joined together, and have latches which fasten them together in light-sealing engagement. A trough, formed of two mating parts, is provided for dispensing the photographic materials therethrough from the chamber. One of the mating parts is a fixed portion of one of the shells, and the other thereof is hingedly joined to the other of the shells. The mating parts of the trough also have latches which fasten them together.
In another example, U.S. Pat. No. 4,597,658, Buelens et al, discloses a light-tight cassette suitable for holding a roll of web-like light-sensitive photographic material wound around a core and for dispensing the photographic material through a slit provided in the cassette which is in the form of a box. The box consists of a hollow shell portion whose wall at three of its corners is at least partly and locally realized as a double wall and two end closure walls which are secured to the shell portion by perforations provided in the outer wall of the double wall portions of the shell and cooperating detent fingers on the end closure walls. The inner wall of the double wall portions of the shell prevents light from intruding into the cassette through perforations in the outer shell wall and makes the cassette perfectly light-tight.
However, these canisters as can be seen from their complex construction are difficult to disassemble and reassemble inside or outside of a dark room environment.
One mechanism which has been used in the past for reusable film cartridges is to have a canister in two pieces with the two pieces being held together with removable pins. The removable pins provide a solid locking mechanism for the canister pieces. However, the removable pins create other problems by creating extra pieces, i.e., the pins themselves, which can be lost defeating the reusability of the canisters. Further, the removable pin arrangement is difficult to use. Disassembly/assembly is made even more difficult in dark room conditions where visible lighting is poor.
U.S. Pat. No. 5,053,795, Wyman, assigned to the assignee of the present invention, discloses an opaque reusable cartridge for storing and dispensing light sensitive web material from a roll. The cartridge is constructed of a right angular sexahedron box made from a top section and a bottom section which are hingedly attached. The cartridge so assembled has limited means for disassembly, making the cartridge difficult to disassemble and reassemble in a dark room environment.